A violent Act or an Act dangerous to human life, in violation of criminal laws of the United States or any segment to intimidate or coerce a government, the civilian population , or any segment thereof, in furtherance of political or social objectives.

Definition of "Terrorism" FBI

the unlawful use of force or violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof in furtherance of political or social objectives.

Terrorist Methods

A desire to further political or social objectives, to target civilian population, with intent to coerce a government or its civilian population

Loosely Affiliated Radical Extremists are neither surrogates of, nor strongly influenced by any one nation. They are considered wild-cards. Examples would be Al Qaeda and affiliated groups such as Abu Sayyaf and Anssar al-Islam.

Trends in international Terrorism

Groups are moving a way from the State Sponsored Terrorism and becoming more autonomous, (Al Qaeda, Hezbolah, PLO, etc)

False multiple passports
no current /fixed address
Materials in possession
Use of Rental or Recently purchased vehicles
Multiple hotel receipts
using all cash transactions
possession of one way travel tickets
disguises